This invention relates to a tire chain for enhancing gripping of a tire in conditions of snow and ice and more particularly to the replacement of worn or broken cross members.
Tire chains as contemplated herein are intended for mounting to driven wheels of a vehicle when a roadway is covered with snow or ice. Mounting to non-driven wheels in addition to driven wheels is optional for maximum control in severe conditions. Additionally, the use of traction devices such as tire chains is required by law when driving on snow and ice covered roads in several states, notably California, Oregon and Washington. Tire chains are not intended for dry road surfaces and the chain""s cross members (which wrap across the tire tread between two side members) will rapidly wear when driven on dry road surfaces. Thus, the chains are to be demounted from the tire as a vehicle enters and exits ice and snow laden road conditions.
A vehicle needs to be driven at a reduced speed when driving on traction devices/tire chains. A chain component that breaks or comes loose can cause damage to the vehicle being driven at a high speed. Even at slow speeds a broken cross member requires that the vehicle be stopped and the tire chain repaired or replaced. The present invention is directed to a releasable securement device for releasably securing cross members to a tire chain side member as when replacing a broken cross member and particularly when cross member replacement is required by the vehicle""s driver while on the road and between destinations.
It is to be understood that the terms traction chains, traction devices or tire chains refer to that product which includes a pair of circular side members designed to extend around the opposed side walls of a tire, the side members connected together by cross members that wrap across the tire tread from side member to side member. (See FIG. 1) The side members may be loops of cable, a steel hoop, plastic, composite material or loops of interconnected links. The cross members may be lengths of cable or lengths of interconnected links or plastic or composite material and the side members and cross members of a given chain may be any combination, i.e., cable cross members and cable side members, cable cross members and link side members, link cross members and cable side members or link cross members and link side members, composite cross members and link side members, cable cross members and steel hoop side members, etc.
The problem of cross member replacement has existed since tire chains were first adopted for enhanced tire traction on ice and snow. The problem has existed particularly for truck drivers having to traverse mountain regions when hauling loads cross country. The sheer weight and power of a large truck both accelerates the wearing of tire chains and the likelihood of cross member breakage when weakened by wearing. It is accordingly not uncommon for truck drivers to have to pull over along snow/ice laden roadways and replace a broken cross member. Not replacing or repairing the chain is not an option as the loose cross member is then whipped around the side of the tire and can wrap around or impact various objects in the vicinity of the wheel and cause immeasurable damage and safety hazards.
Heretofore replacement of cross members typically required the removal or at least the loosening of the tire chain and then the wielding of a large pliar-like tool to force open a metal clamp securement device. A replacement cross member would then have to be secured to the side member again by the wielding of the pliar-like tool to squeeze shut the open clamp. Alternatively, and particularly when the pliar-like tool was not available to a driver, the cross member was repaired in a very temporary manner using a wire wrap or repair link to secure the cross member to the side member. Such was intended only for a temporary fix to enable the driver to limp cautiously to the closest point of shop repair hoping other cross members wouldn""t break along the way.
The preferred embodiment of the present invention provides a secure, finger actuated snap lock-type releasable securement device permanently affixed to each end of a cross member. The cross member as initially assembled to the side member is snap locked to the side members by the securement devices. When replacement is required, the driver merely presses a spring of each securement device to allow disassembly by hand and a replacement cross member is snap locked to the side member in its place. The design of the invention also allows for actuation with common hand tools if desired.
In one embodiment, the clamp is a metal plate that is formed into a hook shape at one end and crimped at the other end onto the cross member. A metal spring (e.g., leaf spring) is anchored to said other end and extends to a position at the opening of the hook shape. A side cable or side link is pressed against the metal spring bending it out of the way as the cable or side link is forced into the hook. The metal spring snaps back to close off the opening and prevents removal of the side member except by intentional deflection of the metal spring.